【作者】 张建军；

【导师】 张永顺；

【作者基本信息】 大连理工大学 ， 机械电子工程， 2012， 硕士

【摘要】 机械臂在航天工程中发挥着重要作用,它们代替人类完成空间对接、未知探索、卫星维护等多项复杂任务。应用于这些场合时对机械臂的控制显得尤为重要,而动作规划与轨迹规划是控制的基础。本文重点介绍了4-DOF采样机械臂的动作规划、轨迹规划和误差分析。本文采用D-H法推导了4-DOF采样机械臂的运动学模型,并对其进行仿真分析。针对该机械臂质量轻、柔性大、负载能力差的特点对其进行动作规划,在此基础上,以肩关节承受的最大静力矩为优化目标,采取极小化极大值法选取六种可能出现最大力矩的情况进行优化。优化结果确定了回转关节每一次动作所需转过的具体角度,并得到最优力矩,满足了设计要求。然后利用SolidWorks软件仿真了4-DOF采样机械臂的全部作业过程,证明了动作规划是合理的。在动作规划的基础上,综合考虑了机械臂的力学特性和工作性质,制定各关节在不同工况下的最大加速度指标。然后用正弦曲线作为各关节轨迹规划的加速度插值函数,分别得到不同工况下各关节承受的最大动力矩以及最大角速度,并计算出机械臂完成全部作业任务需耗时。最后,在运动学分析的基础上,利用齐次变换矩阵法推导了机械臂D-H参数误差与末端执行器误差之间的函数关系。并通过推算机械臂关键动作的误差值,制定了满足设计要求的误差指标。然后,利用Matlab软件对机械臂在特定运动规律和给定误差条件下的末端位姿及误差进行仿真分析,并采用Adams与Matlab联合的手段验证了仿真过程的正确性。更多还原

【Abstract】 Manipulator, which can complete the space docking, unknown exploration, satellite maintenance, and other complex tasks, plays an important role in aerospace engineering. The Control of manipulator is particularly important in these occasions, moreover, trajectory planning is the basis of the control. This paper mainly studies the motion planning, trajectory planning, and error analysis of the4-DOF sample manipulatorThe4-DOF sample manipulator kinematics model is derived by using the D-H method, and simulation analysis for the manipulator is conducted. On this basis of motion planning for the manipulator, the minimax method is adopted to optimize the six selected possible maximum torque according to its light weight, flexible and poor load capacity, aiming to withstand the maximum torque of the shoulder. The optimization results determine the specific point of the rotary joints for every action and the optimal torque. The results meet the design requirements. Then the whole operation process of the manipulator is simulated in SolidWorks to verify the motion planning.On the basis of the motion planning, maximum acceleration indicator of the joints in different conditions is formulated by taking the mechanical properties and the operating characteristics of the manipulator into consideration. Sine curve is used as the interpolation function of the joints trajectory planning. The maximum dynamic torque and angular velocity of the joints in different conditions are obtained. The results show the time to complete all the tasks.Finally, on the basis of the kinematic analysis, the homogeneous transformation matrix method is used to derive the functional relationship between the manipulator’s D-H parameter error and the end-actuator error. The error indicators is formulated by calculating the errors of the manipulator’s key action to meet the design requirements. At last, simulation under specific law of motion and given error condition is taken to analysis the change of end pose and error using Matlab and the simulation is verified based on ADAMS and MATLAB.更多还原